Theodore Epp emphasizes the concept of 'reckoning' in the Christian faith, asserting that it is based on absolute truths rather than feelings or experiences. He explains that believers are to reckon themselves dead to sin and alive to God because of the factual reality of Christ's death and resurrection. Epp reassures that even when believers fail to live out this truth, it does not change the fact of their identification with Christ. He highlights that this transformation from death to life is a one-time event that occurs at the moment of belief, urging believers to trust in God's word regarding these truths.